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427 changes: 427 additions & 0 deletions lib/node_modules/@stdlib/lapack/base/dlanv2/README.md

Large diffs are not rendered by default.

77 changes: 77 additions & 0 deletions lib/node_modules/@stdlib/lapack/base/dlanv2/benchmark/benchmark.js
Original file line number Diff line number Diff line change
@@ -0,0 +1,77 @@
/**
* @license Apache-2.0
*
* Copyright (c) 2025 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// MODULES //

var bench = require( '@stdlib/bench' );
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var Float64Array = require( '@stdlib/array/float64' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
var pkg = require( './../package.json' ).name;
var dlanv2 = require( './../lib/dlanv2.js' );


// VARIABLES //

var opts = {
'dtype': 'float64'
};


// MAIN //

bench( pkg, function benchmark( b ) {
var RT1R;
var RT1I;
var RT2R;
var RT2I;
var CS;
var SN;
var A;
var B;
var C;
var D;
var i;

A = discreteUniform( 1, -50, 50, opts );
B = discreteUniform( 1, -50, 50, opts );
C = discreteUniform( 1, -50, 50, opts );
D = discreteUniform( 1, -50, 50, opts );
RT1R = new Float64Array( 1 );
RT1I = new Float64Array( 1 );
RT2R = new Float64Array( 1 );
RT2I = new Float64Array( 1 );
CS = new Float64Array( 1 );
SN = new Float64Array( 1 );

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
dlanv2( A, B, C, D, RT1R, RT1I, RT2R, RT2I, CS, SN );
if ( isnan( A[ 0 ] ) ) {
b.fail( 'should not return NaN' );
}
}
b.toc();
if ( isnan( B[ 0 ] ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
b.end();
});
Original file line number Diff line number Diff line change
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/**
* @license Apache-2.0
*
* Copyright (c) 2025 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// MODULES //

var bench = require( '@stdlib/bench' );
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var Float64Array = require( '@stdlib/array/float64' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
var pkg = require( './../package.json' ).name;
var dlanv2 = require( './../lib/ndarray.js' );


// VARIABLES //

var opts = {
'dtype': 'float64'
};


// MAIN //

bench( pkg, function benchmark( b ) {
var RT1R;
var RT1I;
var RT2R;
var RT2I;
var CS;
var SN;
var A;
var B;
var C;
var D;
var i;

A = discreteUniform( 1, -50, 50, opts );
B = discreteUniform( 1, -50, 50, opts );
C = discreteUniform( 1, -50, 50, opts );
D = discreteUniform( 1, -50, 50, opts );
RT1R = new Float64Array( 1 );
RT1I = new Float64Array( 1 );
RT2R = new Float64Array( 1 );
RT2I = new Float64Array( 1 );
CS = new Float64Array( 1 );
SN = new Float64Array( 1 );

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
dlanv2( A, 0, B, 0, C, 0, D, 0, RT1R, 0, RT1I, 0, RT2R, 0, RT2I, 0, CS, 0, SN, 0 ); // eslint-disable-line max-len
if ( isnan( A[ 0 ] ) ) {
b.fail( 'should not return NaN' );
}
}
b.toc();
if ( isnan( B[ 0 ] ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
b.end();
});
216 changes: 216 additions & 0 deletions lib/node_modules/@stdlib/lapack/base/dlanv2/docs/repl.txt
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{{alias}}( A, B, C, D, RT1R, RT1I, RT2R, RT2I, CS, SN )
Computes the real Schur factorization of a 2-by-2 real nonsymmetric
matrix using an orthogonal similarity transformation.

Given matrix:

[ A B ]
[ C D ]

The routine computes an orthogonal rotation (cosine CS, sine SN) such
that:

Q^T * [ A B ] * Q = [ AA BB ]
[ C D ] [ CC DD ]

where Q is a 2x2 rotation matrix:

Q = [ CS SN ]
[ -SN CS ]

and the result is either real upper triangular (real eigenvalues) or
2x2 block diagonal (complex conjugate eigenvalues).

Indexing is relative to the first index. To introduce an offset, use
typed array views.

Parameters
----------
A: Float64Array
Input element A(1,1).

B: Float64Array
Input element A(1,2).

C: Float64Array
Input element A(2,1).

D: Float64Array
Input element A(2,2).

RT1R: Float64Array
Output: real part of the first eigenvalue.

RT1I: Float64Array
Output: imaginary part of the first eigenvalue.

RT2R: Float64Array
Output: real part of the second eigenvalue.

RT2I: Float64Array
Output: imaginary part of the second eigenvalue.

CS: Float64Array
Output: cosine of the rotation.

SN: Float64Array
Output: sine of the rotation.

Returns
-------
undefined

Examples
--------
> var Float64Array = require( '@stdlib/array/float64' );
> var dlanv2 = require( '@stdlib/lapack/base/dlanv2' );

> var A = new Float64Array( [ 4.0 ] );
> var B = new Float64Array( [ -5.0 ] );
> var C = new Float64Array( [ 2.0 ] );
> var D = new Float64Array( [ -3.0 ] );
> var RT1R = new Float64Array( 1 );
> var RT1I = new Float64Array( 1 );
> var RT2R = new Float64Array( 1 );
> var RT2I = new Float64Array( 1 );
> var CS = new Float64Array( 1 );
> var SN = new Float64Array( 1 );

> dlanv2( A, B, C, D, RT1R, RT1I, RT2R, RT2I, CS, SN );

> A
<Float64Array>[ 2.0 ]
> B
<Float64Array>[ -7.0 ]
> C
<Float64Array>[ 0.0 ]
> D
<Float64Array>[ -1.0 ]
> RT1R
<Float64Array>[ 2.0 ]
> RT1I
<Float64Array>[ 0.0 ]
> RT2R
<Float64Array>[ -1.0 ]
> RT2I
<Float64Array>[ 0.0 ]
> CS
<Float64Array>[ ~0.93 ]
> SN
<Float64Array>[ ~0.34 ]

{{alias}}.ndarray( A,oa,B,ob,C,oc,D,od,R1,or1,I1,oi1,R2,or2,I2,oi2,CS,ocs,SN,osn )
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need help with the heading here, failing at 80+ characters


Computes the Schur factorization of a 2-by-2 real nonsymmetric matrix
using alternative indexing semantics.

Given matrix:

[ A B ]
[ C D ]

The routine computes an orthogonal rotation (cosine CS, sine SN) such
that:

Q^T * [ A B ] * Q = [ AA BB ]
[ C D ] [ CC DD ]

where Q is a 2x2 rotation matrix:

Q = [ CS SN ]
[ -SN CS ]

and the result is either real upper triangular (real eigenvalues) or
2x2 block diagonal (complex conjugate eigenvalues).

While typed array views mandate a view offset based on the underlying
buffer, the offset parameters support indexing semantics based on starting
indices.

Parameters
----------
A: Float64Array
Input element A(1,1).

oa: integer
Starting index for `A`.

B: Float64Array
Input element A(1,2).

ob: integer
Starting index for `B`.

C: Float64Array
Input element A(2,1).

oc: integer
Starting index for `C`.

D: Float64Array
Input element A(2,2).

od: integer
Starting index for `D`.

R1: Float64Array
Output: real part of the first eigenvalue.

or1: integer
Starting index for `R1`.

I1: Float64Array
Output: imaginary part of the first eigenvalue.

oi1: integer
Starting index for `I1`.

R2: Float64Array
Output: real part of the second eigenvalue.

or2: integer
Starting index for `R2`.

I2: Float64Array
Output: imaginary part of the second eigenvalue.

oi2: integer
Starting index for `I2`.

CS: Float64Array
Output: cosine of the rotation.

ocs: integer
Starting index for `CS`.

SN: Float64Array
Output: sine of the rotation.

osn: integer
Starting index for `SN`.

Examples
--------
> var Float64Array = require( '@stdlib/array/float64' );
> var A = new Float64Array( [ 0.0, 4.0 ] );
> var B = new Float64Array( [ 0.0, -5.0 ] );
> var C = new Float64Array( [ 0.0, 2.0 ] );
> var D = new Float64Array( [ 0.0, -3.0 ] );
> var RT1R = new Float64Array( 2 );
> var RT1I = new Float64Array( 2 );
> var RT2R = new Float64Array( 2 );
> var RT2I = new Float64Array( 2 );
> var CS = new Float64Array( 2 );
> var SN = new Float64Array( 2 );

> dlanv2.ndarray( A, 1, B, 1, C, 1, D, 1,
RT1R, 1, RT1I, 1, RT2R, 1, RT2I, 1, CS, 1, SN, 1 );

> A
<Float64Array>[ 0.0, 2.0 ]
> C
<Float64Array>[ 0.0, 0.0 ]
> RT1R
<Float64Array>[ 0.0, 2.0 ]
> RT2R
<Float64Array>[ 0.0, -1.0 ]
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